Honestly, both ORD and MDW are among the worst spotting airports in the US.

ORD is fair over by Air Cargo, but for sure you will get shagged out in due time, the rest of the area is surrounded by high-traffic roads that are not very desirable in terms of pulling over and spotting.

MDW is well documented for the iron curtain that surrounds the entire property.

A trip to nearby MKE would not be terrible, they have a very nice viewing area on the north end of the airport with ATC patched in over your FM radio. Best in summertime when you have strong south winds.

LGBFltTrainer: Welcome to Chicago! Spotting locations around ORD, while not the most easily accessable, offer great views in good locations, contrary to what others may think. The carmachicago sight is great, however I recommend this site to begin your ORD spotting trips:

The site is a little dated, but it will be a good beginning. The best spot on the website list is #1, is at the 27L approach, at the intersection of Mannheim Rd. and Lawrence Ave., in Schiller Park. There is a dead-end street next to a couple of office buildings. Public street, no reason to get hassled. I spot there during lunch at least once a week. The south cargo area is sketchy, and its on ORD property, so be expecting a visit from the aviation cops if you don't keep a low profile. Another great place is the 22L approach, at the Target parking lot on Mannheim Rd. in Des Plaines. I have never been hassled for spotting at these locations, but I tend to keep a low profile.

Personally, my favorite place to spot is at Wrigley Field on a summer evening. Baseball, airplanes, and, uhh, other treats!

To everyone who responded...thank you!!! This is the information I love...since I've really gotten to enjoy spotting out here in LA (In & Out @ LAX, plus El Segundo hill overlooking 25L & R, AND the parking lot right next to the runway @ LGB), I wanted to get to know the spots out in Chicago...

so, all this information is great...here's hoping to meet some of you folks when I get out there...

If you are down near MDW, the solid fence the Southwest 737 went through at 55th and Central has been replaced by a chainlink fence (it is probably temporary). You can walk right up to it and take pictures, but expect to be chased off by the cops pretty quick.

If the wind is right and they are using 13/31 go to the Giordanos on Cicero and 63rd (on the SW corner of MDW). You can eat some of the best pizza in chicago and watch all sorts of commercial and biz jets fly into MDW. It's a great place to spot. When I used to live in Dubuque we'd fly a cessna into MDW and get a courtesy ride there to eat and watch. It was pretty awesome.